Secondary battery having nonaqueous electrolyte solution

Abstract

Disclosed is a non-aqueous electrolytic solution secondary cell having a negative electrode containing a carbonaceous material capable of occluding and liberating lithium, a positive electrode, a non-aqueous electrolytic solution which includes a solute and an organic solvent, and a separator; wherein the organic solvent contains at least one of compounds selected from those expressed by the formulae (I) and (II) below (in which phi represents a phenyl group optionally having an alkyl group; and R represents any one of a hydrogen atom, C1-4 alkyl groups and a phenyl group optionally having an alkyl group). Such non-aqueous electrolytic solution secondary cell of the present invention is successful in suppressing decomposition of the electrolytic solution, and achieving a high capacity and excellent cycle characteristics.

What is claimed is:  
     
       1. A non-aqueous electrolytic solution secondary cell comprising a negative electrode comprising a carbonaceous material capable of occluding and liberating lithium, a positive electrode, a non-aqueous electrolytic solution which comprises a solute and an organic solvent, and a separator; 
       wherein the organic solvent comprises at least one of compounds selected from formulae (I) and (II) below:                    
       wherein φ represents a phenyl group optionally having an alkyl group; and R represents any one of a hydrogen atom, C 1-4  alkyl groups and a phenyl group optionally having an alkyl group.  
     
     
       2. A non-aqueous electrolytic solution secondary cell as claimed in  claim 1 , wherein the negative electrode further comprises a binder, and the binder comprises at least one rubber selected from the group consisting of styrene-butadiene rubber, hydrogenated styrene-butadiene rubber, styrene-isoprene rubber, hydrogenated styrene-isoprene rubber, isoprene rubber, butadiene rubber and ethylene-propylene rubber. 
     
     
       3. A non-aqueous electrolytic solution secondary cell as claimed in  claim 1 , wherein the organic solvent further comprises a cyclic carbonate or chain carbonate. 
     
     
       4. A non-aqueous electrolytic solution secondary cell as claimed in  claim 1 , wherein the solute is a lithium salt. 
     
     
       5. A non-aqueous electrolytic solution secondary cell as claimed in  claim 4 , wherein the lithium salt is at least one selected from the group consisting of LiClO 4 , LiPF 6 , LiBF 4 , LiCF 3 SO 3 , LiN(CF 3 SO 2 ) 2 , LiN(CF 3 CF 2 SO 2 ) 2 , LiN(CF 3 SO 2 ) (C 4 F 9 SO 2 ) and LiC(CF 3 SO 2 ) 3 . 
     
     
       6. A non-aqueous electrolytic solution secondary cell as claimed  claim 1 , wherein the compounds of formulae (I) and (II) comprise 0.05 to 40 wt % of the organic solvent. 
     
     
       7. A non-aqueous electrolytic solution secondary cell as claimed in  claim 1 , wherein the solute in the non-aqueous electrolytic solution has a concentration of 0.5 to 2 mol/L. 
     
     
       8. A non-aqueous electrolytic solution secondary cell as claimed in  claim 1 , wherein the carbonaceous material has a “d” value (interlayer distance) for lattice plane (002) determined by X-ray diffraction analysis based on the Gakushin-Ho method of 0.335 to 0.340 nm; an ash content of 1 wt % or less; a crystallite size “L c ,” determined by X-ray diffraction analysis based on the Gakushin-Ho method of 30 nm or larger; a median diameter determined by the laser diffraction-scattering method of 1 to 100 μm; a specific surface area determined by the BET method of 0.5 to 25.0 m 2 /g; an intensity ratio “R” (=I B /I A ) of 0 to 0.5, wherein “I A ” being an intensity of peak “P A ” within a wavelength range from 1580 to 1620cm −1  observed in argon ion laser Raman spectrometry and “I B ” being an intensity of peak “P B ” within a wavelength range from 1350 to 1370 cm −1 ; and a half width of the peak within a wavelength range from 1580 to 1620 cm −1  of 26 cm −1  or less. 
     
     
       9. The A non-aqueous electrolytic solution secondary cell comprising: 
       a negative electrode comprising a carbonaceous material capable of occluding and liberating lithium,  
       a positive electrode,  
       a non-aqueous electrolytic solution which comprises a solute and an organic solvent, and  
       a separator,  
       wherein the organic solvent comprises at least one of compounds selected from formulae (I) and (II) below:                    
       φ represents a phenyl group substituted with an alkyl group, R represents any one of a hydrogen atom, C 1-4  alkyl groups and a phenyl group optionally having an alkyl group, and the phenyl group is substituted with an alkyl group selected from the group consisting of methyl, ethyl, propyl, butyl, and hexyl.  
     
     
       10. A non-aqueous electrolytic solution secondary cell comprising: 
       a negative electrode comprising a carbonaceous material capable of occluding and liberating lithium,  
       a positive electrode,  
       a non-aqueous electrolytic solution which comprises a solute and an organic solvent, and  
       a separator;  
       wherein the organic solvent comprises at least one of compounds selected from formulae (I) and (II) below:                    
       φ represents a phenyl group optionally having an alkyl group; and R is a C 1-4  alkyl group selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and tert-butyl.  
     
     
       11. The non-aqueous electrolytic solution secondary cell of  claim 1 , wherein the organic solvent comprises a compound of formula (I) selected from the group consisting of phenylethylene carbonate, diphenylethylene carbonate, methylphenylethylene carbonate, and ethylphenylethylene carbonate. 
     
     
       12. A non-aqueous electrolytic solution secondary cell comprising: 
       a negative electrode comprising a carbonaceous material capable of occluding and liberating lithium,  
       a positive electrode,  
       a non-aqueous electrolytic solution which comprises a solute and an organic solvent, and  
       a separator;  
       wherein the organic solvent comprises a compound of selected from the group consisting of phenylvinylene carbonate, diphenylvinylene carbonate, methylphenylvinylene carbonate, and ethylphenylvinylene carbonate.  
     
     
       13. The non-aqueous electrolytic solution secondary cell of  claim 3 , wherein the cyclic carbonate is at least one carbonate selected from the group consisting of ethylene carbonate, propylene carbonate, and butylene carbonate. 
     
     
       14. The non-aqueous electrolytic solution secondary cell of  claim 3 , wherein the chain carbonate is at least one carbonate selected from the group consisting of dimethyl carbonate, diethyl carbonate, and ethylmethyl carbonate. 
     
     
       15. The non-aqueous electrolytic solution secondary cell of  claim 1 , wherein the carbonaceous material is artificial or natural graphite. 
     
     
       16. The non-aqueous electrolytic solution secondary cell of  claim 1 , wherein the negative electrode further comprises a current collector which comprises a metal selected from the group consisting of copper, nickel, and stainless steel.